Method of treating acne with a c{hd 20 {b acid

ABSTRACT

The C20 and C22 vinylogs of desmethyl retinoic acid have been found highly effective in promoting wound healing, in the treatment of acne, psoriasis and related skin disorders. The acid is applied to the site as a solution, ointment or powder. These acids are the most effective yet found for such purposes yet do not have some of the undesirable side effects of retinoic acid.

United States Patent H91 Lee I May 6,1975

l l METHOD OF TREATING ACNE WITH A C 20 ACID |75| inventor: Kwan-HuaLee. San Francisco.

Calif.

[73] Assignee: The Regents of the University of California. Berkeley.Calif.

[22 Filed: Mar. 2], 1973 [2l I Appl, No.: 343,559

Related U.S. Application Data [63] Continuation-in-part of Ser. No.207.623. Dec. 13.

l97 l. abandoned.

3.729.568 4/l973 Kligman 4Z4/3l8 FOREIGN PATENTS OR APPLICATIONS 901.65)l/l'JbZ 906L000 )llJbZ OTHER PUBLICATIONS Chemical Abstracts I96]. Volp. 7570e. Chemical Abstracts S6; 5l3d. Chemical Abstracts 56; 857le.Chemical Abstracts 56; 39l5d.

Primary h'.\uminerAlbert T. Meyers Ass-(stun! Etumiuer-Norman A. Drezin|57| ABSTRACT The C20 and C22 vinylogs of desmethyl retinoic acid havebeen found highly effective in promoting wound healing. in the treatmentof acne. psoriasis and related skin disorders. The acid is applied tothe site as a solution. ointment or powder. These acids are the mosteffective yet found for such purposes yet do not have some of theundesirable side effects of retinoic acid.

I Claim, No Drawings United Kingdom 424/344 United Kingdom 424x344METHOD OF TREATING ACNE WITH A C20 ACID RPFhRENCF. TO RliLAl'EDAPPLICATION This application is a continuationin-part of my applicationSer. No. 2071i}. filed Dec. I3. 197]. now abandoned.

SUMMARY OI THE INVENTION In accordance with the present invention it hasbeen found that certain desmethyl vinylogs of retinoic acid are highlyeffective in healing wounds and treating skirt disorders such aspsoriasis and acne. The mechanisms involved in the healing ofacne andpsoriasis are not understood but it has been found that the compounds ofthe present invention are highly effective in the trcatment of thesedisorders. It has also been found that the compounds of the presentinvention are highly effecthe in wound healing.

Inflammation and mucopolysaccharide synthesis are the two importantfeatttres in the early stage of wound healing. The term "wound" as usedin this application means any topical lesion such as surgical incision.acci dental wound or ulcer. Aspirin inhibits both features. The healinginhibitory action of aspirin and other inflammatory agents has beendemonstrated. Vitamin A increases m ucopolysaceharidc synthesis and italso causes inflammation. The ability of vitamin A alone to promotehealing and its effectiveness in reversing the healing retardationaction of aspirin is known. Retinoic acid [the acid form of \itamin A)and its salts also have been found active compounds in promotinghealing. Topical application of retinoic acid or its salts reverses thehealing retardation action caused by oral administration of sodiumsalieylate. prcdnisone and other antiintlammatory agents and topicalapplication of salicylic acid or hydrocortisonc. Topical application ofretinoic acid and its salts promotes skin wound healing in rats andhuman beings.

Rctinoic acid has been used in the treatment of psori asis. acne. andrelated dermatological conditions such as Darier's disease. ichthyosis.hyperkeratoses. pityria sis. and pseudofolliculitis ofthe heard. Theexact mechanism of action of retinoic acid is unknown; however. thenormali1ing" effect on keratinization that occurs is seen concomitantlywith irritation which is character iZed by redness and peeling of theskin. In fact. it is believed that retinoic acid may have to beirritating to be effective in acne. In psoriasis. the beneficial actionof retinoic acid is limited by its irritant effect. Additionally, mostof the other agents used to treat psoriasis-antimetabolitcs. tars.anthralin-are not used more frequently because of their potential forirritation.

It has now been found that Z.b.6.-'Irimethyl-l-( ltlcarboxy-decal, 3' 5'7 W-pentaenyll cyclohexl-ene acid and 2.b.h.-'Irimethyl-l-(lZ'-carboxydodeca-l' 3 5' 7' 9' ll"hexaeny'll cyclohex- I-ene acid areeven more effective than vitamin A or vitamin A acid for wound healing.The corresponding C l b and C l X acids have also been made and testedbut they are considerably less effective for this condition than the Cand C 22 acids of the present invention. These latter compounds havebeen shown to be effective in the treatment of psoriasis. acne. andrelated skin conditions. Furthermore. the acids of the present in\ention have been found to be considerably less toxic Ill fill

and have fewer side effects. even when used at higher concentrationsthan retinoic acid.

It is very practical to dust these compounds on the body or to applyeither of them as a solution or in an ointment. The C120 acid ispreferred.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The topical application of (10or C22 acids has been found to promote wound healing. This is true bothof animals which have not been otherwise treated and also true ofanimals which have been treated with antiinflammatory agents such as asalicylate. hydrocortisone. prednisone. indoniethacin. mefenaniic acidand the like. These compounds normally retard healing and C20 and C22acids reverse this action. The C20 and C22 acids also are effectiveagents in the treatment of psoriasis and acne.

PREPARATION OF THE COMPOT'NDS The following is one method of preparingthe novel C20 and C22 acids ofthc present inxention. In the sy nthesisselected. beta ionone is first comerted to an aldehyde having lo carbonatoms and this is reacted with triethylphosphonocrotonate to produce the('20 ethyl ester and this is hydroly7ed to the desired Cit) acid. It isalso possible to go directly from the C l I aldehyde to the CZU ester byemploying a phosphono compound having eitht carbon atoms with conjugateddouble bonds. One route for preparing the C2] acid is through the Cltlacid.

PREPARATION OF BETA (l2 ACID At tl pass 84 grams of chlorine gas into4th! ml of IUM sodium hydroxide solution. To which. at room temperature.add 6-1 grams of beta ionone. Stir for 3 hours. Add Xi) ml of methanoland maintain the temperature below 85C by adding crushed ice and thenbring the pH to about 4 by adding phosphoric acid. Cool to roomtcmperatre and the beta C12 acid will rise to the surface and can befiltered with the aid of suction. The crude acid is then dissolved inEU? aqueous sodium hydroxide solution and extracted with ether. Theaqueous solution is acidified with phosphoric acid and again extractedwith ether. The ether extract is dried with anhydrous magnesium sulfate.The ether is evaporated and the acid is recrystallized from methanolsolution to provide the purified C12 acid.

PREPARATION OF Cl 2 ALCOHOL Ten grams of lithium aluminum hydride isplaced in a 3 necked flask under a nitrogen atmosphere and 50 ml ofanhydrous ethyl ether is added and stirred with a magnetic stirrer atl5C. Dissolve 51) grams of the CIZ acid previously prepared in anhydrousether and add slowly into the flask containing the lithium aluminumhydride. The temperature should be maintained below minus ltlC. Afterall ofthe acid has been added. the temperature can be allowed to rise toroom temper ature and kept at this temperature for l hour. The mix" tureis then cooled to 0 and IN sulphuric acid is added until bubbles ceaseto form. The temperature should be maintained below 5C. The reactionmixture is filtered and the precipitate washed with ether. The etherlayer is separated and washed with water and is then dried withanhydrous magnesium sulfate and the ether e aporated. The yield is about9301' of theory.

PREPARATION OF (l2 ALDEHYDF.

In the following reaction. acti ated manganese dioxide is used which canhe prepared either hy the method of Attcnhurrow et al .1. Chem. Soc.lllV-lt 1951i or (arpino. J. Org. (hent \'ol. 35 No. ll lll7ll) 397l.

Ahout 5U grams of the ('11 alcohol in ('(I solution is placed in adropping funnel attached to a two-liter llaslt. Slll) grams of activatedmanganese dioxide and llllll) ml of anhydrous carhon tetrachloride areplaced in the flask and stirred. The l 1 alcohol solution is now slowlyrun into the manganese dioxide suspension and stirring is continued atroom temperature for 2 hours after all of the alcohol has heen added.The mixture is filtered and washed with carbon tetrachloride and theextract is then dried and e aporated. The yield is ahout )5; of theoryPRFPARA'] ION OF (lo ESTER Weigh 47 grants of a sodium hydride in oildispersion (57'; NaHl and place it in a two-liter llask. Wash withanhydrous ether. Add llllltl ml of anhydrous tetrahydrofuran tTHFl andcool to lero. One then places 140 grants of triethylphosphonoerotonatein a dropping funnel and adds it dropwise to the sodium hydridesusension with stirring. Stirring is continued at lero de grecs forone-half hour after all the crotonatc has been added About fill grams ofthe (l2 aldehyde dissolved in l'Hl is now slowly added and warmed toroom tem perature and allowed to stand at room temperature oier onehalfhour. The mitture is then cooled to zero and one adds a saturated sodiumchloride solution to destroy the excess of sodium hydride. The mixtureis now extracted with petroleum ether and the extract dried to evaporatethe solvent. yielding the desired ester.

PREPARAl ION OF (m ACID The ester is hydrolyzed by refluxing it in alll't potas sium hydrosidecthanol solution under nitrogen for 4 hours.The mixture contains 5t] grams of the ester. 5t) grants ol'potassiuinhydroxide. 3tlll ml of water and Ztlll ml ofetlianol. After thehydrolysis is completed. acidify the ini\turc. The acid can he extractedwith ethyl ether.

PREPARATION OF (Ill AND (22 ACIDS The detailed procedure for ohtainingthe (Ill from the (in acid is not giyen since the reactions aresuhstantially the same as outlined aho e. 'l'he (lo acid recmered fromthe last step is comertcd to the alcohol. utilizing lithium aluminumhydride and this is con- \erted to the corresponding aldehyde utili/ingmanganese dio\ide as dcscrihcd aho\e. 'l hc aldehyde now is reacted withtriethylphiisphonocrotonate to produce the (It) ethyl ester and this inturn is hydroly/ed as de- .scrihed ahine to produce the (Ill acid of thepresent imention. l'he ('1: acid can he prepared from the (Ill acid hyusing the al1o\c method and employing the triethylphosphontnicctate.

(Ill or (11 acids can he applied in the form of an ointment as asolution in oil or as a powder. In each instance a concentration ofahout lllt' has been found suitahle although larger or smallerconcentrations may he used. Below ahout ll.lll. 2 the effectivenessfalls off and increasing the concentration to l to 2'; increases (illthe effectiveness only slightly; a concentration of about ll l'r'.whether in an ointment. oil solution or powder. is ahout optimum.

Suitahle oil carriers include physiologically accept ahle oils in whichthe acid is soluble such as isopropyl :nyristate. corn oil. cottonseedoil and the like. Powder can he prepared utilizing the CEO or C22 acidcrystals by grinding the crystals with a suitahle inert carrier such astalc. Clll or (22 acid can be combined with any of the usual ointmenthases used in pharmacy. One suitahle hase is known as NIB tnon-ionicbase) devel oped by the University of California School of Pharmacy anda suitable formulation has the following approximate composition:

('12 acid 2"? (ctyl alcohol 6 Stearly alcohol 6 White petrolatum l-lLiquid petrolatum Ill Methyl parahen (H5 Propyl parahen our Polysorhaletill 5 l Polyosyl 4t) stearate 5 Propylene glycol I Puril'lcd water aslllll;

Other suitahle cream. gel and lotion hases that can be formulatedfollow:

USE OF COMPOUNDS IN WOUND HEALlNG (iridlay and Waugh (Arch. Surg. (13.288 (1951] used granuloma formation induced by polyyinyl sponge to studytissue regeneration. Since then this method has heen used as a standardmethod to study would healing. Dunphy and his associates (Ann. NY. Acad.Sci. 86. 943 t lllill) ha\e pointed out that the repairment ofconnective tissue is the most basic feature in wound healing. and theyused granuloma formation techniques in their many wound healing studies.

This method in olyes suhcutaneous implantation of cotton-pellets andmeasuring the size of the granuloma induced after a few days.Anti-inflammatory agents reduce the size or weight ofgranuloma ascompared with that of the control. Those compounds which promote healingincrease the size or weight of the granuloma.

(irowth of granulation tissue into cotton-pellets was induced hysubcutaneous implantation at two symmetrical dorsolateral sites ofSprague-Dawle v male rats weighing Ill) i 5 g under ether anesthesia.

lhe cotton-pellet implanted on the right side coir tains the compoundunder test and the cotton-pellet each of the agents being tested. lhecompounds under test were applied in tLUZ'i concentration in a baseconsisting of 50; propylene glycol and 50') ethanol. The followingresults were obtained:

implanted on the left side ser\ es as the control. l'he 5 compound wasintroduced to the pellet as its ether sovs RFfl'lNUlC ACll) lution. Theether was completely evaporated before implantation. On the seventh dayafter implantation. the Suhiect wk 2 \\c' .'h .1 LLl\\ ommt-iu animalswere killed with ether and the both weights I no ellcct R It! R'( e -iimprovement were taken. lhe granulomas were carclull removed In 3 R.(gl) (3 1 lmpmuqwul and weighed rapidl on a torsion balance. Afterdrying a if is $2117 ""lz fl s": in an oven at 65C for 48 hours thedried slices were 5 T 5 weighed. The following results were obtained.

EFFECT OF 3.7'-DESMETHYI. RFTINOK ACID \"INYLOGS ON (O'II'ON-PFLLINDUCED (iRANL'LOMA IN RATS (iranuloma lixpt. (jranuloma lixpt. Wet Wt.mg. Control Drv Wt. mg. Control No. of Acids lispt. Expt. (iroup AnimalsApplied Control Control 1 a A shrill 29.0121

Zofiztll l.l 371:1! l.l H H H Lltl-Ht 43.|t2.h

ll1'i.tl*5.9 l5 25.5 2L5 l.7 Ill 43 430.213.] fiflfitlj 205.012.? 2.2 23911).) 2.9 I\' It) I) 373.91%.6 60.5:lfv

202914.11 1.x l-L'Jrlj 2 4 A Acid: 2. b. b. lrimethvk l b'-carbox hesa-l3'. It was concluded that the ('20 acid of the present in- 5'trien vllcvclohev-l ene. vention had suhstantiall greater effectiveness in most BAcid: 2. -'l ritneth vl-l-t3'-carlmsv-octa-| 3' instances than retinoicacid. The compound of the l 'ilv l l cy h -ln present in\ention didappear to act more slowl than desmethvl retinoic acid. retinoic acid.since after week those lesions treated C Acid: 3. (1. (1.-'l'rimethvll-l ltl'-carboxv-decal' with retinoic acid appeared to hemore imprmed How .5 7' .T-pentaenvl) cyeIohe\-leneever. at theconclusion of the tests. four out of the five D Acid: 2. 6. (i.-'l'rimeth vl-l-l l2'-carbox 'dodcca- 1 subjects of the (Ill acid of thepresent invention were .3 5 .7 9 .l l hesaen \l) cvclol1ex-l-ene.clearly superior to retinoic acid while in one instance It is believedapparent from the foregoing that the it was equal to it. C20 and (I2acids of the present invention (Acids C and D in the table) are highleffective for wound heal- [SE OF (:OMPOFNDS [N THE TRFATMFN'I' OF mg andare much more eltective than the homologs ACNE having to or [8 carbonatoms. The (EU acid is somewhat more effective than the C22 acid.

Further tests established that the (20 and C21 acids ln another seriesoftests the eomedolvtic effect ofthe are not toxic or at least not astoxic as retinoic acid. (2U acid of the present invention was comparedwith Retinoic acid inhibits embryonic chick tibia growth that ofretinoic acid. In this series of tests. rabbits were while (20 and C22do not. Retinoic acid. at higher dos- 5 employed as a test modelv 'l'hecomedogenic property age (4 mg/IUU g rat) inhibits growth. The ('20 ateven of various chemicals on rabbit cars has been demonhigher dosages t8tug/100g rat) does not inhibit strated b v Kligman (Arch. Derm. \ol. )8.Jul v I968. growth. pp. 53 and 5X lhis' acneigenic effect parallels thatin n human skin and that he reduced by effective antiacne Lisp 0|"(OMPOUNDS IN IRhAIMhNI OF 55 drugs. Thus. this animal model has servedas a reliable PSORIASIS screen for agents that may he used to reducecomedo- The following tests were made to show the effectivees in humanaena ness of these compounds in the treatment of chronic The cars of therabbits were treated for 2 weeks with psoriasis. Five patients wereutilized: each of the pait); crude coal tar. which produced eoniedonesltlis' tients had a histor of chronic stable psoriasis which hit tensionofthe follicles with impacted horn) \cr similar had proved more or lessresistant to topical steroid to that in human acne. Without treatment.these cometherapy. In this series of tests. the (:0 acid of thepresdones do not change over the next 2 weeks. (oncentrte ent inventionwas compared with retinoic acid (desigtions of 0.1? and (H054; of thecompound in 5H; nated R in the tablet and the test agents were appliedpropylene glycol/5091' ethanol were applied once daily to one or twoequivalently matched lesions on opposite ,5 for a period of 2 weeks.After 2 weeks of treatment. the

sides. 3 times dail for a weeks. No other therap was utilized. At theend ofeach week an experienced therapist made an evaluation of therelative effectiveness of experienced observer can estimate the degreeof reduction in size of the impaction that has been achieved. The degreeof healing was scored on a scale of five wherein zero equaled no change.one equaled a slight decrease. t\\o equaled a moderate decrease. threeequaled a great decrease. and -l equaled complete abolition of comedonesThe following data were obtained:

(Ill \s RHIINOK' Afll) Rabblt (oneentratlon (III Relinoie Acid l tl ll Fi 2 n t, 1 1 s n in 1 3 -l ll ll:, I 2 s n U15" l 3 0 ll H15, 1 I

It \\'ill be seen from these data that in each instance the (2H acid asat least as effective as retinoic acid and in some instances it wassubstantiall better Howe\er it did ha\e a great advantage in that it wasless ir Ill (ill

ritating Retinoic acid produces erythema and scaling in the rabbit ear:histologieally an infiltration by neutrophiles can he observed. The (Illcompound of the present invention was grossly and histologically lessirritating to the tissue. Normally in itselfthe retinoic acid is notvery effectixe in the treatment of acne unless it produces peeling andredness. The compound of the present imention has the healing effect ofretinoic acid without the irritation effects I claim: I. A method oftreating an acne condition comprising;

applying topically to the affected area of a patient having an acnecondition. an amount effective for treating said acne condition. oflfib-trimethyl-l lltl-carbosy-deca-l', 3' ,5 ,7 '-)'-pentaen'l)cyelohex-Lene in combination with a ph \siologically acceptablecarrierv

1. A METHOD OF TREATING AN ACNE CONDITION COMPRISING: APPLYING TOPICALLYTO THE AFFECTED AREA OF A PATIENT HAVING AN ACNE CONDITIONS, AN AMOUNTEFFECTIVE FOR TREATING SAID ACNE CONDITION, OF2,6,6-TRIMETHYL-1-(10''-CARBOXY-DECA-1'', 3'' ,5'' ,7'',9''-PENTAENYL)CYCLOHEX-1-ENE IN COMBINATION WITH A PHSIOLOGICALLYACCEPTABLE CARRIER.